OBJECTIVEThe aim of the study was to investigate whether Orai1 antibody intraperitoneal injection could improve the condition of allergic rhinitis (AR) in mice.

METHODSTwenty-four BALB/C mice (SPF grade) were classified into 4 groups (AR group, Control group, Experimental group 1 and experimental group 2) according to a random number table. A mouse model of AR was established (Control group was established by phosphate buffered solution), and experimental group 1 and Experimental group 2 were established through intraperitoneal injection of 100 μg and 150 μg Orai1 antibody respectively. The number of sneezing and rubbing and eosinophilia in mice were assessed after different doses of Orai1 antibody intraperitoneal injection were applied. Then Orai1 protein and its mRNA in nasal mucosa, histomine, eosionphil cation protein (ECP), interlukin (IL)-1β, IL-4, IL-5 and IL-6 and their mRNA in nasal lavage fluid (NLF) and nasal mucosa were evaluated using enzyme linked immunosorbent assay (ELISA) and real-time reverse transcription-polymerase chain reaction (real-time RT-PCR). Furthermore, Orai1 protein and its mRNA in Th2 cells in peripheral blood, IL-4 and IL-5 in peripheral serum and their mRNAs in Th2 cells were also examined through ELISA and real-time RT-PCR. The data were analyzed by a statistical software of Graph Pad Prism 5.

RESULTSThere were significant differences in sneezing, nasal rubbing and local invading eosinophils in nasal mucosa after the treatment (t100 μg=7.88, t100 μg=9.92, t100 μg=4.30, respectively; t150 μg=16.43, t150 μg=16.31, t150 μg=9.35, respectively, all P-values<0.01). The Orai1 antibody intervention decreased contents of Orai1 in nasal mucosa, histomine, ECP, IL-1β, IL-4, IL-5 and IL-6. The contents of experimental group 1 were (0.186±0.015) μg/ml, (6.618±0.180) ng/ml, (2.555±0.031) ng/ml, (85.26±2.94) pg/ml, (55.12±1.21) pg/ml, (58.45±2.11) pg/ml and (77.12±2.13) pg/ml, respectively. The contents of experimental group 2 were (0.089±0.003) μg/ml, (4.501±0.310) ng/ml, (1.260±0.017) ng/ml, (48.49±2.12) pg/ml, (33.15±0.87) pg/ml, (38.24±0.95) pg/ml and (51.72±0.81) pg/ml, respectively. The differences were siginificant between group 1, group 2 and AR group(t value was 3.29, 10.44, 9.45, 17.53, 74.53, 87.06, 3.98; 8.54, 13.32, 23.00, 20.89, 80.73, 103.70, 13.34, all P<0.01). However, there were no significant differences in Orai1 protein and its mRNA in peripheral Th2 cells, IL-4 and IL-5 in peripheral serum and their mRNAs in Th2 cells (all P-values>0.05). In addition, the effect of 150 μg Orai1 antibody treatment was better than 100 μg one (all P-values<0.05).

CONCLUSIONOrai1 antibody intraperitoneal injection can improve the symptoms of AR mice, and alleviate the condition of allergic inflammation. Orai1 may become a novel aim in the AR study.